Noise stress during pregnancy has been reported to be embryolethal, as well as teratogenic, in rats and mice. However, there have been few studies concerning the possible effects of prenatal noise stress on the development of neurobehavioral functioning of the offspring; although a combination of light and heat stress has been reported to cause changes in catecholamine levels in brain areas affecting sexual differentiation of adult rats exposed as fetuses and to cause demasculinization of male offspring. The purpose of this experiment is to determine the effects of prenatal noise stress on neurological functioning and reactivity of offspring. The results of these experiments might be used in the planning of future studies that (1) compare the effects of noise stress to other stressers, (2) determine the role of stress-induced release of catecholamines in the medication of any long-term behavioral effects and (3) measure those changes in neurochemical and neuroendocrinological status in stress exposed animals that may be correlated with any behavioral changes.